Colm is shown as a lean, elderly man with long grey hair, weathered skin, and gritty stubble on his face. In his few appearances, he is usually seen sporting a somewhat similar outfit to Dutch, albeit in his gang's color scheme, with a black double-breasted waistcoat decorated with gold buttons and a gold watch chain. He wears black trousers, a white pinstriped shirt, a patterned green neckerchief, black finger-less gloves, and a black hat with a snakeskin band.

He also sports a fur-lined coat.